Elevating conveyer



.April 20, 1943. w. H THQMA 2,317,313

E'LEVATI-NG CONVEYER Filed Nov. 12, 1942 FIG. 1

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Patented Apr. 20, 1943 UNITED STATES FATENT OFFICE ELEVATING CONVEYER William H. Thoma, Pittsburgh, Pa. Application November 12, 1942, Serial No. 465,331

- versely to conform to the path. Near its top the 10 Claims.

This invention relates to endless conveyers, and more particularly to elevating conveyersby which semi-solids and free-flowing solids may be lifted from one level to another and then automatically discharged from the conveyer.

Conveyers of this character generally are formed from an endless chain traveling in a conduit a portion of which is substantially vertical. The chain carries vanes or flights by which mate rial is elevated in the vertical portion of the conduit until it reaches a lateral opening through which it is discharged from the flights. However, some materials do not readily leave the flights in the discharge area, so an undesirable amount of the material is carried past and over into the back leg of the conduit. This decreases the capacity of the conveyer. It can be avoided to some extent by driving the chain at a lower speed, but that obviously decreases the capacity of the conveyer in another way. When light comminuted material such as flour and powder are carried by the conveyer they become aerated when discharged from the flights and form a cloud of material some of which follows the chain past the discharge opening and back to the loading point, thus decreasing the capacity of the conveyer in the same way as material that sticks to the flights.

It is among the objects of this invention to provide an elevating conveyer which has high capacity, which assures discharge of substantially all material from the conveyer flights at the unloading point, which substantially prevents aerated material from following the chain into the back leg of the conduit, which is simple in construction, which presents practically no danger of the chain becoming jammed or pulverizing lumps of material carried by it, and which is formed to reduce the friction of the material against the sides of the vertical portion of the conduit.

In accordance with this invention, an endless chain travels through a conduit having a vertically disposed portion or riser. The chain travels up through the riser and over chain-supporting means mounted in the top of the conduit. Material-liftingflights are connected to the chain in such position that the chain carries the flights edgewise around the chain-supporting means after the flights leave the riser. By edgewise is meant that the flights at that time are substantially perpendicular to the radius of their arcuate path of travel. In case the flightsare flat they would be substantially tangent to that path, but it is preierred to'icurve them trans conduit has a lateral discharge outlet'directly above which there is a transverse partition provided with an opening for the passage of the chain and flights. This opening is located in the path of the flights'as they travel edgewise around the chain-supporting means so that the opening can be restricted in size and considerably smaller than the cross sectional area of the riser. The opening thus is made about as small as possible to leave but little chance for the material to be carried into the back leg of the conveyer. The conveyer is most suitably constructed with the flights bifurcated or divided into two parts so that they straddle the chain. Each flight is mounted on the outer end of an arm rigidly connected to one of the chain links. The arms likewise may be bifurcated, in which case they straddle the chain. The relation of the flights to the chain is such that the conduits lower portion, that is curved laterally away from the riser portion to a loading opening, may be of smaller cross sectional area than the riser. This is desirable because it limits the capacity of the conveyer at the location in which it is loaded to a volume that is less than the capacity of the riser. The result is that the material is not pressed tightly against the sides of the riser, so friction is reduced, thereby decreasing power consumption and wear on the riser.

The preferred embodiment of the invention'is illustrated in the accompanying drawing in which Fig. 1 is a side view of my conveyer with the conduit shown in vertical section; Fig. 2is an enlarged horizontal section taken approximately on the line II-II of Fig. 1 but showing one of the conveyer flights passing through the transverse partition opening; Fig. 3 is an enlarged horizontal section taken on the line III-III of Fig. 1; Fig. 4 is a front view of a link and arm and flight just starting to pass around the sprocket at the top of the conduit; and Fig. 5 is a side View of the integral unit shown in Fig. 4.

Referring to Fig. 1 of the drawing, an endless conveyer conduit is shown having a vertical front leg or riser l and an adjoining back leg 2 connected at their lower ends by a laterally curved loop having vertically spaced upper and lower portions. The top of the lower portion: is provided with a loading opening 3 to which material may be delivered in any. suitable manner. A double idler roller 4 is journaled in the end of the loop, while a double driving sprocket" 5 is similarly mounted in the upper, end of the conduit. r

Traveling through the conduit and around the sprocket and roller is an endless chain by which material-lifting flights I are elevated through the riser. Each flight is connected to a link 8 of the chain by an arm 9 that is rigidly connected to' both. In fact, it is preferred to cast the link and arm and flight as a single unit as shown in Figs. 4 and 5. Each arm is joined to the bifurcated rear end of a link and projects rearwardly therefrom at an obtuse angle. The arm preferably is double so that it can extend along both sides of the following link, the two links being connected together by a pin l passing through their adjoining ends. The rear end of each link has laterally projecting cylindrical bosses I I through which pin l0 extends and which are adapted to be engaged by theteeth oi the double sprocket at the top of the conduit. Likewise, each flight is divided transversely into two laterally spaced parts so that it can straddle the adjacent link and move back and forth across it as the chain travels around curves.

Another feature of this invention is that each flight is inclined to the longitudinal axis of the link, to which it is connected, at such an angle that the flight is moved into a position substantially perpendicular to the axis of the sprocket when the flight starts to travel around it. The flight at that time will therefore travel edgewise, and as its relation to the sprocket is fixed as long as both ends of the adjoining link are engaged by the sprocket, the flight will travel in an arcuate path concentric with the sprocket. For a reason that will appear presently, it is preferred to curve the flights transversely to the same curvature as that arcurate path so that the thickness of the path will be no greater than the thickness of any flight. The inclination of the flights relative to the chain links will depend upon the length of the links and arms 9 for any given sprocket. The greater their length the less the inclination. Links and arms of a length that require the flights to be disposed at about 45 to the vertical when traveling up through the riser conduit are generally preferred.

Directly below sprocket on the up-strearn side the conduit is provided with a discharge opening in its side wall. Between this opening and the sprocket there is a partition wall in the conduit provided with an opening 2! for passage of the traveling conveyer elements through the partition. As shown in Fig 1, this partition preferably is formed by the inwardly sloping top wall of an open-sided casing 22 projecting into the conduit through the discharge opening and forming a discharge chamber and chute. The outwardly sloping bottom wall 23 of the casing likewise has a. central inlet 24 from the top of the riser for passage of the chain and flights. As shown in Fig. 3, the casing is wider than the flights and contains a pair of laterally sloping surfaces 25 behinditsinlet opening 24 to divide the material discharged from the flights and direct it down bottom wall 23 past the opposite sides of the inlet. The inclination of the flights facilitates discharge of material from their rear edges as they enter the casing.

The top wall of the discharge casing extends across the arcuate path traveled by the flights around the sprocket in order to take advantage of the fact that, as previously explained, the flights move edgewise along that path. Thus, as shown in Fig. 2, the portion of the partition opening 2! through which the flights pass need be only a slot wide enough to receive the flights edge wise,

rather than a large rectangular opening such as casing inlet 24. Also, it will be noted that the flights do not pass through the same part of outlet 2| as the chain, but at one side of the chain, so the chain-receiving portion can be made small enough to merely permit the passage of the chain with its projecting bosses 5 5. These two parts of the outlet are connected by a narrow portion through which the arms 9 pass as they are swung outwardly away from the sprocket. The partition opening therefore is substantially r shape with a considerably smaller total area than inlet opening 24. The area of this opening is further decreased by a horizontal bar 28 attached to the top of the discharge casing and projecting inwardly :part way across the flight and arm-receiving portion of the opening to close the space between the two parts of each flight and arm. This bar also serves as a guide to accurately position and steady the chain and flights as they pass through the partition; I

There are two principal advantages that aris from the restricted opening 2i in the top of the discharge casing. Due to the fligh -receiving part of the opening being a narrow slot, partition wall 20 acts as a scraper that cleans the flights passing through the slot and thereby prevents material adhering to the flights from escaping from the casing and into the :back leg of the conduit. Another important advantage is that opening 2| is so restricted in size that even during the short intervals when it is not substantially closed by the traveling elements of the conveyer its area is so small that there is no chance for any appreciable amount of aerated material in the discharge casing to escape through partition 26).

It will be observed that the curvature of the portion of the conduit below the riser is such that the rear ends of arms 9 are not allowed'to swing away from the adjacent links 8 and leave a space between them. If that were done, solid material might lodge between the arms and adjacent links and be pulverizedwhen the arms swing back across the chain in the riser conduit.

The construction of the traveling elements of this conveyer also permits the curved portion of the conduit between its inlet 3 and the riser to be made narrower than the riser. This is desirable because it allows the conveyer to be loaded to capacity at the inlet, and yet when the material enters the wider riser conduit the material is given more room and therefore does not produce so much friction against the side walls of the riser. The result is that less power is required to drive the conveyer. i 7

This conveyer carries full loads and partial loads equally well. It can be driven at high speed without any'added danger of carrying some of the material over the sprocket. The conveyer is flexible in opposite directions so that it can be readily adapted to any desired location.

According to the provisions of the patent statutes, I have explained the principle and construction of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced Otherwise than as specifically illustrated and de scribed.

I claim:

1. An elevating conveyer comprising a conduit having a substantially vertical portion with a lateral discharge outlet near its upper end, an endless chain traveling through the conduit, material-lifting flights connected to the chain, chain'- supporting means in the conduit above said outlet and around which the chain travels, said flights being so positioned relative to the chain that it carries them edgewise around said supporting means, and a partition Wall above said discharge outlet provided with an opening for the chain and flights, said opening being restricted in size and snugly receiving the chain and flights as the flight travel edgewise around said supporting means whereby said opening is materially smaller than the cross sectional area of said vertical portion of the conduit so that substantially no material being conveyed can pass said partition wall.

2. An elevating conveyer comprising a riser conduit, an endless chain traveling up the conduit, material-lifting flights connected to the chain, rotatable means above the top of the conduit and around which the chain travels, said flights being so positioned relative to the chain that it carries them edgewise around the rotatable means, and a discharge casing between the rotatable means and the top of the riser conduit, said casing being, provided in its bottom with an inlet from the top of the conduit and in its top with an outlet opening for the chain and flights, said outlet opening being restricted in size and snugly receiving the chain and flights as the flights travel edgewise around said rotatable means whereby the outlet is materially smaller 5 than the inlet so that substantially no material being conveyed can escape from the casing through said outlet.

3. An elevating conveyer comprising a conduit leaving a substantially vertical portion with a lateral discharge outlet near its upper end, an endless chain traveling through the conduit, material-lifting flights connected to the chain, chain-supporting means in the conduit above said outlet and around which the chain travels, said flights being so positioned relative to the chain that it carries them edgewise around said supporting means in an arcuate path, and a partition wall disposed across said path and provided with an opening for the chain and flights, said opening being restricted in size and snugly receiving the chain and flights whereby it is materially smaller than the cross sectional area of said vertical portion of the conduit so that substantially no material being conveyed can pass said partition wall.

4. An elevating conveyer comprising a riser conduit, an endless chain traveling up the conduit, material-lifting flights connected to the chain, a rotatable member above the top of the conduit and around which the chain travels, said flights being so positioned relative to the chain that it carries them edgewise around the rotatable member in an arc concentric therewith, each of the flights being curved transversely to conform to said arc, and a discharge casing between the rotatable member and the top of the conduit, said casing being provided in its bottom with an inlet from the top of the conduit and in its top with an outlet Opening for the chain and flights, said outlet opening being in the path of the flights as they travel edgewise in said arc, and the outlet having a portion for snugly receiving the chain and another narrow flight-receiving portion spaced from its chain-receiving portion whereby the outlet is materially smaller than the inlet so that substantially no material being conveyed can escape from the casing through said outlet.

5. An elevating conveyer comprising a riser conduit, an endless chain traveling up the conduit, material-lifting flights connected to the chain and each being divided transversely into two spaced parts, a rotatable member above the top of the conduit and around which the chain travels, said flights being so positioned relative to the chain that it carries them edgewise around the rotatable member, a discharge casing between the rotatable member and the top of the conduit, said casing being provided in its bottom with an inlet from the top of the conduit and in its top with an outlet opening for the chain and flights, said outlet opening being restricted and snugly receiving the chain and flights as the flights travel edgewise around said rotatable member, and a bar projecting part way across said outlet opening and adapted to be straddled by each twopart flight as it passes through the outlet.

6. 'An elevating conveyer comprising a riser conduit having a substantially vertical upper portion and a laterally curved lower portion of less width provided at its lower end with a loading opening, an endless chain traveling up the conduit, material-lifting flights connected to the chain and substantially engaging the opposite sides of the vertical portion of the conduit, said flights being so related to the chain as to be able to pass through said restricted curved portion of the conduit, a rotatable member above the top of the conduit and around which the chain travels, said flights being so positioned relative to the chain that it carries them edgewise around the rotatable member, and a discharge casing between the rotatable member and the top of the conduit, said casing being provided in its bottom with an inlet from the top of the conduit and in its top with an outlet opening for the chain and flights, said outlet opening being in the path of the flights as they travel edgewise around said rotatable member, and the outlet also being restricted in size and snugly receiving the chain and flights whereby it is materially smaller than the inlet so that substantially no material being conveyed can escape from the casing through said outlet.

'7. An elevating conveyer comprising a riser conduit, an endless chain traveling up the conduit and formed from pivotally connected links, a rotatable member above the top of the conduit and over which the chain travels, a plurality of material-lifitng flights each positioned substantially perpendicular to the radius of said rotatable member when it passes over said member, an arm rigidly connecting each of said flights to an adjacent chain link, and a discharge casing between the rotatable member and the top of the conduit, said casing being provided in its bottom with an inlet from the top of the conduit and in its top with an outlet opening for the chain and arms and flights, said opening having separate portions for snugly receiving the chain and arms and flights as the flights start to travel over said rotatable member whereby the outlet is materially smaller than the inlet so that substantially no material being conveyed can escape from the casing through said outlet.

8. An elevating conveyer comprising a conduit having a substantially vertical portion with a lateral discharge outlet near its upper end, an endless chain traveling up the conduit and formed from pivotally connected links, chainsupporting means in the conduit above said outlet and over which the chain travels in an arouate path, a plurality of material-lifting flights each positioned substantially perpendicular to the radius of said path when the flight passes over said means, an arm rigidly connected to each link and projecting rearwardly therefrom with its rear end rigidly connected to one of said flights, and a partition wall above said discharge outlet provided with an opening for the chain and arms and flights, said opening having separate portions for snugly receiving the chain and arms and flights as the flights start to travel through said path whereby said opening is materially smaller than the cross sectional area of said vertical portion of the conduit so that substantially no material being conveyed can pass said partition wall.

9. An elevating conveyer comprising a conduit having 'a substantially vertical portion with a lateral discharge outlet near its upper end, an endless chain traveling up the conduit and formed from pivotally connected links, chainsupporting means in the conduit above said outlet and over which the chain travels in an armate path, a plurality of material-lifting flights each curved transversely and being concentric with said arcuate path when the flight passes over said means, an arm rigidly connected to the rear end of each link and projecting rearwardly and laterally therefrom with its rear end rigidly connected to one of said flights, and a partition wall above said discharge outlet provided with an opening for the chain and arms and flights, said opening having separate portions for snugly receiving the chain and arms and flights as the flights start to travel through said path whereby said opening is materially smaller than the cross sectional area of said vertical portion of the conduit so that substantially no material being conveyed can pass said partition wall.

10. An elevating conveyer comprising a riser conduit, an endless chain traveling up the conduit and formed from pivotally connected links, a rotatable member above the top of the conduit and over which the chain travels, a plurality of material-lifting flights each positioned substantially perpendicular to the radius of said rotatable member when it passes over said member, a bifurcated arm rigidly connected to the rear end of each link and straddling the following link, each of said flights being bifurcated and rigidly connected to the rear end of one of said arms with the flights straddling the adjacent link, and a discharge casing between the rotatable member and the top of the conduit, said casing being provided in its bottom with an inlet from the top of the conduit and in its top with an outlet opening for the chain and arms and flights, said opening having separate portions for snugly receiving the chain and arms and flights as the flights start to travel over said rotatable member whereby the outlet is materially smaller than the inlet so that substantially no material being conveyed can escape from the casing through said outlet.

WILLIAM H. THOMA. 

